The work routines of many tradesmen today require that tools and materials be brought to the job and moved around the job location; and that some work be performed on a workbench. For work such as heavy maintenance, plumbing or carpentry the tools are heavy and numerous. Supplies such as plaster buckets, paint cans, pipe fittings and the like add weight and heft to the worker's on-the-job materials. Many tradesmen transport their tools and supplies in a pick-up truck, thus having to load and unload these items daily, To meet the tool and supply handling needs of diverse workers and tradesmen, a wide variety of work site utility carriers are used.
When tradesmen have to move tools and material around at the work site, the usual transport means is a dolly typically having four wheels and some kind of handle for pulling and steering. The numerous tools themselves must be organized and quickly available for use, and virtually all tradesmen therefore use a portable, lockable metal toolbox. On occasion it is also necessary to move articles besides tools and supplies around the work site that cannot practically be loaded and carried on a dolly, such as a desk, plywood sheets, or a washing machine. For this task a sturdy hand truck is needed.
Work sites typically require a work bench or table as well. This item too must therefore be available on the site to the workman wherever the need for a work table arises. All of these worksite utility items—the dolly, the toolbox, the hand truck and the work table—must be not just transportable to the site but also must be readily loadable across the tailgate of the tradesman's pick-up truck and rolled into position in the truck bed.
Some of the prior art utility carriers usefully combine the functions of a hand truck and a tool cart. Examples are U.S. Pat. No. 2,964,328 issued 13 Dec. 1960 to Muir; and U.S. Pat. No. 5,224,531 issued 6 Jul. 1993 to Blohm which also includes a work surface. Hand trucks with permanently mounted tool carts or boxes are exemplified by U.S. Pat. No. 6,170,839 issued 9 Jan. 2001 to Kizewski which also has a dolly mode and a flat work surface; and by U.S. Pat. No. 5,566,659 issued 31 Dec. 1996 to Boes et al. U.S. Pat. No. 5,419,569 issued 30 May 1995 to Walls shows a hand truck outfitted with a storage container and capability to carry heavy cylinders using straps. Many hand trucks include a pivoted or extendable flat surface to provide a work bench. Examples are U.S. Pat. No. 2,784,004 issued 3 Mar. 1957 to Hamrick and U.S. Pat. No. 4,934,718 issued 19 Jun. 1990 to Voegele. The hand truck of U.S. Pat. No. 6,341,788 issued Jan. 29 2002 to Ciccone also shows a dolly mode that optionally provides an extendable work table. U.S. Pat. No. 6,758,482 issued 6 Jul. 2004 to Stallbaumer slows a hand truck-dolly combination with detachable handles, work surface and tool tub that may be placed in a raised or lowered mode.
Some hand trucks are convertible by various means to a fuller work bench. U.S. Pat. No. 5,642,895 issued Jul. 1, 1997 to Wunder shows a hand truck with retractable legs enabling conversion into a work table. U.S. Pat. No. 5,203,815 issued 20 Apr. 1995 to Miller is a conventional hand truck-dolly that mounts a detachable work table top. U.S. Pat. No. 5,957,472 issued 28 Sep. 1999 to Borgatti is a collapsible hand truck and machine stand. U.S. Pat. No. 6,530,583 issued 11 Mar. 2003 to Mueller shows a dolly for wheeling a power saw attached to a support that swings to the horizontal to provide a table saw when the dolly is tipped upright. The folding work bench/tool table of US patent application publication 2002/0179181 of Dec. 5, 2002 by Murphy combines a dolly frame that mounts a removable tool box, A work table is hinged to two rear legs pivotally mounted on the dolly rear castor frames and two front legs hinged at the dolly frame midsection. The table is held by lockable braces either in an upright mode or a lowered mode in which the table secures the tools.
While the preceding prior art work site utility carriers each offer some versatilities and multiple uses, none provide the full functionalities of a hand truck, a retractable work bench, a safe place to store tools, and a dolly. Moreover, none provide a mechanism specifically adapted to allow the utility carrier to be loaded readily by a tradesman into and out of the bed of a pick-up truck.